Tag Archives: moa

Episode 050: Tallest Animals

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We’re discovering which animals are the tallest this week! This episode includes our first dinosaur!

Sauroposeidon proteles:

Giraffes:

Bop bop bop have at thee!

Paraceratherium (I couldn’t find one that I liked so I drew one, along with a giraffe and ostrich to scale):

Ostrich running:

I SAID DON’T @ ME

A fine day at the ostrich races. I could not make this stuff up if I tried:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re looking at tall animals. Is the giraffe the tallest mammal that’s ever lived? Is the ostrich the tallest bird? And what about tall dinosaurs?

I don’t talk about dinosaurs much in this podcast because there are so many good podcasts devoted specifically to dinosaurs. I recommend I Know Dino. It’s family friendly and goes over the latest dinosaur news without talking down to listeners or dumbing down the information.

Four-footed animals are usually measured at the shoulder, since some animals hold their heads low, like bison, while others hold their heads high, like horses. But we’re talking about tall animals today, and that includes animals with long necks. So the measurements here are all from head to toe, with the head and neck held in its natural standing position.

Let’s start with the real biggie, the tallest dinosaur ever found.

In 1994 a guy named Bobby Cross noticed some fossils weathering out of the ground at the Oklahoma correctional facility where he worked as a dog trainer. As he always did when he found fossils, he called the Oklahoma Museum of Natural History. They sent a team to take a look. The team found four vertebrae, but they were just so big—around four feet long each, or 120 cm—that at first they thought they must be fossilized tree trunks.

Sauroposeidon proteles was probably closely related to Brachiosaurus, but was even bigger and taller. Sauroposeidon stood 60 feet tall, or 18 meters, and its neck alone was 39 feet long, or 12 meters. Its body and legs were relatively short and stocky. We don’t have a complete skeleton, just the four vertebrae found in southeastern Oklahoma, and a few vertebrae from two other individuals found in Montana and Texas. A trail of giant footprints in Texas may be a Sauroposeidon track too. But for sauropods, neck vertebrae are the most valuable fossils because they tell so much about the animal.

Sauroposeidon’s neck bones were massive, but they were lighter than they look due to tiny air sacs in the bones, like those in bird bones. The air sacs in bird bones actually contain air that flows through the lungs, called pneumatic bones, which provides the bird with more oxygen. A CT scan of the Sauroposeidon fossils—at least the portions of the fossils that would actually fit in the CT scanner—revealed that sauroposeidon’s vertebrae were constructed in the same way that bird bones are. We know that pterosaurs and theropods had pneumatic bones, so it’s not too surprising that at least some sauropods did too.

Sauroposeidon lived around 110 million years ago, during the Mesozoic era, specifically during the early to mid Cretaceous. The sea level was much higher then than it is now, so Sauroposeidon lived near the coast. It ate plants, and like many birds, it also swallowed stones to help it digest those plants, called gastroliths. Paleontologists have found lots of sauropod gastroliths associated with fossil animals. Unlike mammals, which chew their food before swallowing, sauropods swallowed it whole and the plant material was broken up in a stomach or gizzard-like structure. That’s why its head is so small relative to its body, and how it could eat enough plants to keep such an enormous body going. It probably ate literally a ton of food every single day.

We know a lot about sauropods, and since sauroposeidon appears to be structurally typical of other sauropods, just really big, it’s a safe bet to assume it was like other sauropods in many ways. It probably nested in groups and laid about two dozen eggs at a time in big nests on the ground. We don’t have any sauroposeidon eggs, but they probably wouldn’t have been all that big, maybe about the size of a football. Babies would have grown rapidly and were full grown in ten to twenty years. Sauroposeidon migrated in herds throughout the year, traveling from nesting grounds to new grazing grounds. While it lived near the ocean, it would have had to be careful about walking on soft ground. An animal that tall and heavy can get mired in mud easily. Paleontologists have actually found fossils of sauropods that died standing up, unable to climb out of a muddy hole after sinking in soft ground.

Giraffes are the tallest living animals today, with the tallest recorded giraffe, a male, measuring 19.3 feet, or 5.88 meters. That’s pretty darn tall, about 1/3 the height of sauroposeidon. Giraffes are related to deer and cattle, and live in the savannahs and forests of Africa, where they eat tree leaves that are much too high off the ground for other animals to reach. Female giraffes and their young make up loose groups, while males form groups of their own. While giraffes can kick hard enough to kill lions, when males fight over females, they use their necks. A male will swing its head at another male, and the two will tussle back and forth bopping necks together. As a result, male giraffes have thicker, stronger necks than females. Males are also usually taller than females.

The giraffe not only has a long neck and long legs, it has a long tongue that it uses to grab leaves that are juuuust too far away. The tongue is about 18 inches long, or 45 cm. A giraffe at Knoxville Zoo licked my hair once. The giraffe’s upper lip is also prehensile, and is hairy as a protection from thorns. Because of all the thorns it encounters, giraffe skin is surprisingly tough. The giraffe has large eyes that give it good vision, and it also has keen hearing and smell. It can close its nostrils to protect them from dust, sand, insects, and—you guessed it—thorns. So many thorns. And giraffe fur contains natural parasite repellents, which also makes giraffes smell funny.

All this is pretty awesome, but we’re not done with giraffe awesomeness. Giraffes have skin-covered horns called ossicones. Females and males both have ossicones, although males also have a median lump at the front of the skull that’s not exactly an ossicone but is sort of like one. Some females also have this median lump. Ossicones are made of cartilage that has ossified, or turned boney, and they’re covered in skin and hair, although since males use their ossicones in necking fights, they tend to rub all the hair off and have bald ossicones.

The only other animal alive today that has ossicones is the okapi, a close relative of the giraffe, but giraffe ancestors once had all kinds of weird ossicones. Xenokeryx amidalae, for instance, which lived about 16 million years ago in what is now Spain, had two ossicones over its eyes, and a third sticking up from the back of its head that was T-shaped. The name amidalae comes from the character Padme Amidala in Star Wars: The Phantom Menace, if you remember that weirdly shaped headdress she wore.

Because giraffes are so tall, they have some physical adaptations that are unique among mammals living today. A giraffe has the same number of neck bones as all other mammals except sloths and manatees, which are weird, but the vertebrae are much longer than in other mammals, almost a foot long, or 28 cm. The giraffe can also tilt its head right back until it’s just about in line with the back of the neck. I’m picturing everyone listening tilting their heads back right now, and hopefully you notice how the back of your neck curves when you look up. Also, please don’t wreck your car because you’re looking up while driving. The giraffe’s circulatory system is really unusual. Its heart is enormous and beats around 150 times per minute. The jugular veins, which are the big veins that carry blood up the neck to the brain, have valves that keep blood from running backwards when a giraffe lowers its head to drink.

Giraffes can walk, and giraffes can run, but they don’t have any other gaits. They can’t trot or canter, for instance. Even humans have more than two gaits, because we can skip. Despite its height, a giraffe can really move. It can run over 30 miles per hour, or about 50 km per hour, and keep it up for several miles. It has cloven hooves. Because a giraffe’s body is so heavy and its legs so long and thin, it has specialized ligament structures in its legs that keep them from collapsing. Horses also have this structure, which also helps the animal sleep while standing.

Oh, and the giraffe doesn’t eat leaves all the time. It spends a lot of the day just standing around chewing its cud.

There used to be a mammal that stood almost as tall as the giraffe at the shoulder. Paraceratherium orgosensis went extinct around 23 million years ago, and it’s not even related to the giraffe. It’s a member of the rhinoceros family. Like sauroposeidon, we don’t have a complete skeleton of paraceratherium, so its size is an estimate based on the proportions of closely related animals whose sizes we do know. It probably stood 18 feet high at the shoulder, or 5.5 meters, and while its neck was probably around 7 feet long, or a little over 2 meters, it probably held it forward like a rhino instead of up like a giraffe, so it didn’t add much to the animal’s overall height.

In episode 32 we learned about the giant moa, a flightless bird that once lived in New Zealand. It was probably the tallest bird that ever lived, with big females 12 feet tall, or 3.6 meters. But the tallest living bird is the ostrich. It also lives in Africa and is famous for being flightless and for being able to run really fast. In fact, it’s not only the tallest bird alive, it’s the fastest. It can run over 40 miles per hour, or about 70 km per hour, and it uses its large wings as rudders and even to help it brake. With its head raised, a big ostrich can be nine feet tall, or 2.8 meters.

There are a lot of differences between ostriches and most other birds. Most birds have four toes, for instance. The ostrich has two, one large toe with a hoof-like nail, and a smaller outer toe with no nail at all. All other living birds secrete urine and feces together, but the ostrich secretes them separately the way mammals do. And while most male birds don’t have a penis, the male ostrich does. And the ostrich has a double kneecap. Not only is that unique to birds, it’s unique to everything. No other animal known, living or extinct, has a double kneecap. Researchers have no idea what it’s for, although one hypothesis is that it allows a running ostrich to extend its legs farther, and another hypothesis is that it might protect tendons in the bird’s leg.

The ostrich eats plants, seeds, and sometimes insects. Like Sauroposeidon and many other dinosaurs and birds, the ostrich swallows small rocks and pebbles to help digest its food in its gizzard. The gizzard contracts, smashing the gastroliths and plants together to help break up the plant material the way mammals would chew it.

Ostrich eggs are the biggest laid by any living bird, about six inches long, or 15 cm. Females lay their eggs in a communal nest.

Ostriches are farmed like big chickens, for their feathers, meat, and skin for leather. Ostriches are also sometimes ridden and raced with special saddles and bridles. But ostriches aren’t easy birds to manage. They can be aggressive, and they can kill a human with one kick.

To wrap things back around to dinosaurs, some researchers think many fast-running dinosaurs used their feathered forelimbs the way ostriches use their wings, to help maneuver and possibly to help keep unfeathered portions of the body warm at night. During the day, when it’s hot, ostriches keep their wings raised so that their unfeathered upper legs can release heat into the atmosphere, but at night they cover their upper legs to retain heat. It’s just another link between birds and their long-distant ancestors, the dinosaurs.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 032: Some New Zealand birds

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This week’s episode is about several New Zealand birds, from the still-living kiwi to the mmmmmaybe extinct moa! Note: I’m going to start putting a full transcript of each episode in the show notes for those who would like to know what words I’m mispronouncing and for those who may have hearing issues. Transcripts will be below the pictures.

A kiwi:

Superman has fought everything.

The controversial blurry “moa” picture taken by Freaney. Probably not a moa.

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Before we get started, apologies for my voice. About the time I finally got over the cough I picked up at WorldCon in Finland, I went to DragonCon in Atlanta and got a big juicy cold. Hopefully I don’t sound too gross. My traveling for the year is over so I’m looking forward to having time to really dig into some fun topics for the podcast. In particular, I’m going to be covering some of the creepier strange animals in October, because Halloween is the best. And yes, Bigfoot is going to make an appearance.

This week’s episode is about some amazing birds from New Zealand. We learned about the takahe way back in episode seven, a big silly-looking flightless bird that was once thought extinct until its rediscovery in the middle of the last century. This week we’ll look at some other birds, some of them happily alive, some that are definitely extinct. At least, we’re pretty sure they are.

New Zealand wasn’t settled by humans until the late 13th century, only about 750 years ago. That’s mind-blowing until you take a look at a globe. New Zealand isn’t just a hop skip and jump away from Australia, it’s 900 miles away over open ocean. It’s 600 miles away from the Pacific Islands. That’s a long, long trip to make in a small boat, especially when you’re not sure if there’s any land out that way. But sometime between the years 1250 to 1300, people from eastern Polynesia discovered this new land. They liked it and stayed, and their descendants are now known as the Maori.

I know we’ve been talking about tectonic plates in a number of episodes recently. I haven’t done it on purpose—it’s just part of learning how and why different animals developed in different places. It’s definitely relevant when it comes to New Zealand.

New Zealand is just a little part of an otherwise submerged continent called Zealandia, or sometimes Tasmantis, which I actually prefer. Tasmantis. If Zealandia weren’t mostly under the ocean, it would be about half the size of Australia. Around 90 million years ago Zealandia, Australia, and Antarctica were all part of the supercontinent Gondwana. As Gondwana broke up, Zealandia separated from Antarctica and Australia around 80 million years ago, then slowly sank into the ocean.

After Zealandia separated from Gondwana, a cataclysmic event, probably a humongous meteor strike, led to the extinction of some 85% of the animals on earth. In most of the world, mammals began to evolve like crazy to fill the vacant ecological niches after the dinosaurs died off. But Zealandia didn’t have very many mammals to start with, and by 25 million years ago it was mostly underwater anyway except for the peaks of New Zealand, which were being pushed up slowly by tectonic forces—a process that’s still ongoing.

When travelers from Polynesia first landed on New Zealand, the only mammals on the islands were three species of bat. But there were birds in abundance, from enormous moas and eagles to tiny kiwi. Almost every ecological niche was filled by a bird.

Europeans first visited New Zealand in 1642. It didn’t go well and no one came back until 1769, and after that things got messy and lots of people died from war and introduced diseases. Around the mid-19th century Europeans started moving to New Zealand. Between them, the Maori, and introduced mammals like rats and dogs, a whole lot of birds went extinct.

I just want you to know that it took me hours and hours and hours to research all that stuff about Zealandia. Hopefully I got it right. I’m ready to talk about birds now.

Let’s start with a bird that is so unique to New Zealand that you’ll sometimes hear people call New Zealanders kiwis. There are five species of kiwi, all of them rare and protected. They’re round brown poofs of birds with long legs and long bills, and they eat worms, insects, seeds, fruit, frogs, and other things like that. They prefer to live in forests and usually mate for life, and can live for 50 years.

The kiwi has a lot of unusual characteristics. It’s flightless but has wings less than an inch long hidden under its feathers. Each wing has a tiny claw at its tip that doesn’t seem to have a use. The kiwi has no tail. Unlike every other bird out there, its nostrils are at the tip of its bill. The kiwi has a good sense of smell and may detect worms and other underground prey by smell, which should make you pause and wonder what earthworms smell like. The kiwi also has sensory pits at the tip of its bill that helps it detect vibrations, though, so it’s possible its good sense of smell is less important than researchers previously thought. When a kiwi detects its prey, it stabs its bill into the ground to catch it, which frequently leads to the kiwi later having to snort dirt out of its nostrils. Evolution does what it can, folks, but it’s not perfect.

Since it can’t fly and doesn’t need flight feathers, the kiwi’s feathers are hair-like and downy. But most curious of all is its egg. The kiwi is about the size of a chicken, but its egg is six times the size of a chicken egg and can weigh an entire pound. It’s so big that the female can’t even eat the last few days before she lays the egg. There’s no room in her body for food.

After the female lays her egg, the male incubates it. That huge egg has a huge yolk to feed the baby inside, so when the baby kiwi hatches, it’s ready to go. After a few days it leaves the nest and starts foraging, usually with its dad alongside for the first few weeks. It takes several years for it to grow to adult size.

The kiwi is territorial and will fight other kiwis that stray into its territory. Only its mate and its own offspring are allowed in its territory. It has powerful legs with claws that can inflict quite a bit of damage, and it can run faster than a human.

Scientists used to think the kiwi was closely related to moas, which we’ll talk about in a minute, but DNA studies have determined that its closest relative is the extinct elephant bird of Madagascar—and the elephant bird is the topic for a future episode.

The Maori describe a huge black swan called a Pouwa that lived in the Chatham Islands, but it had already gone extinct by the time Europeans arrived in the area in the late 1700s. Until recently researchers thought it was just the Australian black swan, either a population that lived in New Zealand or the occasional individual that flies across the Tasman Sea. Australian black swans were introduced to New Zealand in the 1860s.

But a recent study of DNA from fossilized swan remains from New Zealand show that it wasn’t the same bird as the Australian black swan but a related species. Around one or two million years ago Australian black swans lived in New Zealand and evolved into a separate species, heavier than the Australian birds with longer legs and shorter wings. It might have been a poor or reluctant flier and might have been on its way to evolving into flightlessness before it was eaten into extinction by the Maori.

The big name in extinct birds of New Zealand is the moa. Nine species of moa are recognized today, although in the past researchers thought there were a lot more. It turns out that female moas of some species were much larger than the males, so much so that scientists once thought they were looking at two different species. Moas were big flightless birds that in shape resembled big flightless birds from other parts of the world, known as ratites, which includes ostriches. Until DNA testing most researchers thought moas were closely related to the ratites of Australia, emus and cassowaries. But no, they are most closely related to a group of birds from Mexico, Central America, and South America collectively called tinamous. Tinamous are a type of ratite, but they can fly. They’re all fairly small and somewhat resemble quail and other game birds that spend a lot of time foraging on the ground.

Moas, however, are big. They are really big. Originally scientists mounted their skeletons so that the neck stuck more or less straight up, but now we know that they held their necks more like ostriches, with a gentle S-shaped curve. Even so, females of the biggest species, the South Island Giant Moa, stood around six and a half feet high at the back. That doesn’t even count the neck. With the neck outstretched, a big female moa could probably reach leaves twelve feet off the ground.

All moas were plant-eaters. Some ate leaves and fruit, others were adapted to digest tougher plant material like twigs, moss, and bark. Unlike other flightless birds, they didn’t have wings at all, not even for display, not even vestigial wings. They just flat-out didn’t have forelimbs. They did have strong legs although they probably couldn’t run very fast, unlike other flightless birds like ostriches. After all, moas didn’t need to run to escape predators. They only had one predator, and that was one they couldn’t outrun: Haast’s eagle.

Haast’s was the biggest eagle that ever lived, although its wings were comparatively short—only around 10 feet wide for big females, closer to 8 ½ feet wide for big males and more average-sized females. Since much of its hunting range was forested, its shorter wings probably helped it maneuver. It had a long tail too. But it had enormous talons with claws over four inches long, and its bill was similarly big. In fact, its talons were so big that its scientific name, Harpagornis moorei, means Moore’s grappling hook bird.

The Haast’s eagle’s prey was the moa, and when moas went extinct after overhunting, the Haast’s eagle went extinct soon after since it just didn’t have anything to eat. It did apparently try to adapt its hunting habits, though. Maori legends tell of the Pouakai, an enormous bird that would sometimes kill humans.

It’s pretty certain that Haast’s eagle is extinct. If it was still around, ranchers would spot it picking off sheep and calves. But the moa is something else. Moa sightings pop up pretty frequently in remote areas of New Zealand.

One of the smallest species of moa, Megalapteryx, also called the upland moa, may have survived on the south island until the mid-19th century. The upland moa was three or four feet tall including the head and neck, and was completely covered with feathers except for its bill and feet, since it lived in the mountainous areas of New Zealand’s south island where the climate was cool. It laid one or two blue-green eggs a year and the male took care of the babies.

Its accepted date of extinction is around the year 1500, but there have been numerous sightings since then. In 1880, Alice McKenzie, who was then seven years old, saw a three-foot-tall bird with blue feathers, dark green scaled legs, and three claws on each foot. She ran to get her father, but when they returned the bird had gone, although it had left big tracks in the sandy soil. She saw the same bird again in 1889.

The problem with this sighting is that the upland moa had feathered legs, and as far as we know no moas had blue plumage. We have plenty of upland moa feathers, which are grey, black and white. We even have mummified upland moa remains. Not only did Alice describe her bird as blue, she specifically noted it was the blue of a pukeko, which has vibrant plumage that varies from navy blue to violet. This wasn’t a grayish-blue bird. Alice herself thought, later in life, that she might have seen a takahe, which is also blue, but after the takahe was rediscovered she went to view some and was disappointed. They have red legs and she knew her bird’s legs were green.

But that’s not the only sighting. In addition to the sporadic accounts of big birds seen in the distance, in 1993 three men hiking in the Craigieburn Range saw what they described as a red-brown and gray moa some six feet high, including its neck. It ran off when it saw them, but one of the men, Paddy Freaney, ran after it and managed to get a photograph. He also got a few pictures of its footprints where it had stepped in a stream and then on a rock.

The picture is frustrating, to say the least. It’s so out of focus that it could be anything. However, I agree with one of the experts who have examined the photo, palaeoecologist Richard Holdaway, who says the figure’s neck is too thick for a moa. He thinks the picture is probably of a red deer. As far as I can find, Freaney’s photos of the footprints haven’t been released.

In 2007, a pair of cryptozoologists searching for moas in the hill country of the North Island spotted 35 footprints and what appeared to be a nest that they claimed were made by a group of moas, possibly a lesser moa. But considering that the pair of cryptozoologists are Rex and Heather Gilroy, who are notorious for being secretive, vague in their claims of evidence, and somewhat paranoid about their findings, I don’t expect them to show up with a live moa anytime soon. No other moa sightings or even rumors of moas living in the area have ever been uncovered.

It’s easy to dismiss this account, and the others, as wishful thinking, misidentification, and in some cases maybe outright hoaxes. Australian emus are raised in some areas of New Zealand and sometimes escape from captivity, too, which confuses the issue, since emus are big flightless birds that could easily be mistaken for moas at a distance. But there is something that makes me hopeful that the moa might still be around, especially one of the smaller species.

New Zealand’s south island is much less populated than its north island. Alice McKenzie’s sighting in 1880 was on her family’s farm near Milford Sound, which is now part of Fiordland National Park. This is a big nature reserve in the southwest corner of the south island, with rugged terrain and very few tracks passable to even offroad vehicles. The park includes the Murchison Mountains, which is where the takahe was rediscovered in 1948 after being thought extinct. So it’s entirely possible that a small species of moa might be hiding in the area. Maybe one day someone will get a really good picture—or better yet, a hiker or park ranger might come across a newly dead moa carcass and can bring it back for study.

We do have some subfossil moa remains that aren’t just skeletons and feathers. Dessicated body parts turn up occasionally, which has helped with DNA testing and our knowledge of what the living birds looked like. The moa is a good candidate for de-extinction by genetic cloning, and it would be really neat to have moas for sure running around in New Zealand again, so scientists can get right on that as far as I’m concerned.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on iTunes or whatever platform you listen on. We also have a Pattreon if you’d like to support us that way. Rewards include stickers and twice-monthly bonus episodes.

Thanks for listening!